Some Common misconceptions in Science, Maths and Technology

Hello people!

This time I am here to talk about some of the misconceptions (in science, maths and technology) that we are still bearing. So, without waiting anymore let’s go through the points given below.

1. Planets revolve around the sun

This one is most likely to be believed by almost all of us because this is what what we have been taught so far. Haven’t we? Well, the textbooks issued by the government can’t be wrong, in general. However, they can be inaccurate.

So, what I mean to say is that planets don’t precisely seem to revolution around the sun. They rather revolve around the barycentre. In fact, the sun itself revolves around it. In astronomy, the barycentre is defined as the centre of mass of two or more bodies that orbit one another and it is also the point about which the bodies orbit.

Since, the sun is composed of 99.9% of the mass of the solar system, it’s quite obvious to think that the barycentre of our solar system lies inside the sun, near its geometrical centre and that’s what which makes it appears that the planets to revolve around the sun. However, to make this point clear, in illustrations the distance between the barycentre and the geometrical centre of the sun is often exaggerated. Similarly, it’s not precise to say that the moon revolve around the earth, but it is better to say that they both revolve around their barycentre. For a deeper insight, check out this website of NASA.

2. More megapixels means better camera

Trust me people, if you think so then you are badly mistaken and you are also likely to be fooled by some smartphone companies.

The performance of a camera doesn’t solely depends on its megapixels (sensor resolution) but on its image processing, the size of the sensor and the aperture too. For instance, consider the two latest phones, iPhone 11 and Xiaomi Mi Note 10. iPhone 11 has a rear camera of only 12MP whereas Xiaomi Mi Note 10 has a rear camera of a whopping 108 MP. However, there is a huge difference in the quality of images produced by them in low light (which is indeed a parameter used in defining the quality of a camera). The former one performs better than the latter in spite of having comparatively lower megapixels. Here are some sample pictures captured by the two phones.

Clearly, iPhone 11 stands out.

3. Chameleons change their skin colour in order to camouflage

This is another widely believed myth. According to some latest researches, chameleons do so in order to express their moods, response to changes in temperature, attract their potential mates and to react to any physical pressure applied on their body.

Chameleons don’t need to change their body colour on order to camouflage because they already have some amazing body features like 360° eye view.

To know more about this, consider watching this video.

4. √4 = ±2

Consider the following two equations,

1) x= √9

2) x²= 9

What do you think would be their solutions? Most likely, you would think that both of them will have ±3 as their solution, probably, because you believe that we write the both positive and negative roots of a number which is under the radical symbol (i.e. √ ). If you think so, I am afraid, you are wrong.

The symbol √ (the square root radical) means the principal square root i.e the positive root only. Therefore, the solution of the first equation is just 3 (and not -3).

If you notice the second one, you would find that it’s a quadratic equation, and we know, a quadratic equation always has two roots (they may either be distinct, equal or imaginary). Thereby, the solution of the second equation is ±3 (this can also be verified using Shreedharacharya’s quadratic equations formula).

In the above graph for y=√x , you can clearly see the graph doesn’t spread out in the second, third and fourth quadrant. This means that both x and y can’t be negative.

Thus, x= √9 = 3 …(no -3)

Whereas, x²= 9

=> x = ±√9 = ±3

5. The absolute refractive index of a material is same for all colours of light

This one is more of a consequence of ignorance than a misconception, I believe. Textbooks up to secondary school level seem to ignore this crucial fact that the absolute refractive index (or simply the refractive index) of a material depends on the wavelength of the light rays too.

So, if we say that the absolute refractive index of water is 1.33, we need to mention the fact that it’s a average value. The value of refractive index of water is different for different colour of lights. Some of the values are given below.

It’s clear that the value of absolute refractive index of a material depends on the wavelength of the light in question.

The same is true for the refractive index of a material with respect to another.

6. Current can’t flow without a potential difference

This one is something that we come to conclude intuitively. So, again, it is something to be called a consequence of ignorance rather than a misconception.

Here, I mean to say that a current can still flow even when the potential difference between two points in space is zero.

Let’s understand it mathematically,

By ohm’s law we have

V=IR

So, if V =0

Then, IR=0

Therefore, either I =0 or R=0 or both

Now, if we put R = 0, then clearly, I ≥ 0

Thus, a current can exist even when potential difference is zero.

That’s why we never talk of potential difference while defining current. In very simple words, current is nothing but a flow of change.

For a deeper insight, you may like to check out Dr. HC Verma’s lecture on this.

7. Using a cell phone at a petrol pump is a fire risk

The signs at a petrol pump make it pretty obvious – don’t use your phones while filling up the tanks. The only risk you’re taking when filling the tank while talking on the phone is that you’re distracting yourself. There have been no recorded facts about a phone causing a fire at a gas station. Instead of completely neglecting your phone, just be careful with yourself and your actions.

8.We have five senses
Besides the five empirical senses (sight/visual, sound/auditory, touch/tactile, taste/gustatory, and smell/olfactory), there are at least four other senses that are rarely cited: proprioception- sensing one’s orientation in space; thermoceptionsense of temperature; equilibrioception- sense of balance; and interoception-sense of one’s physiological condition. The next time someone talks about their “5 senses,” you can say that you have “9 senses” and then sit back and let them think you have superpowers.

9. Moist air is heavier than dry air

Contrary to our common belief, air leaden with moisture is lighter than dry air. We can work out the reason for this as follows:

Oxygen and nitrogen make up more than 98% of the atmosphere. Also, the molecules of water are lighter than the molecules of oxygen and nitrogen. Furthermore, when new and lighter molecules are introduced in the air, they tend to replace some of the existing heavier molecules in the air (i.e. the molecules of nitrogen and oxygen). This means that when a given volume of air is made more moist by adding water molecules, heavier molecules are replaced with lighter molecules. Therefore, moist air is lighter than dry air if both are at the same temperature and pressure

10. The space is empty

Though the we often hear that the space is vacuum (or empty) but it turns out that it isn’t. A vacuum is defined as a space devoid of all matter. In the Solar System, space contains on average five atoms per 1cm³. Interstellar space, between stars, contains around one atom per 1cm³, while intergalactic space, between galaxies, contains 100 times less. The solar wind emitted by the sun (and other stars) fill up the space with protons on average of 5-10 of them per cm³. It contains antimatter and dark matter too.

Furthermore, the space isn’t quiet and devoid of energies either. The formations of virtual particles are always happening which creates some sort of fluctuations in the space, called quantum fluctuations. The space is also filled with negative and dark energies. According to astrophysicists, there is also a possibility of finding loops called wormholes in the space.

The so called empty space isn’t empty at all at the quantum level.

So, in short, in contrast with our common notion about space, it isn’t quite empty. Watch this video for more information on this.

That’s all I had for you in this segment. I hope you enjoyed reading this article. I also believe that you must have got new things to learn and up till now, some of the myths that have been bearing are debunked.

Thank very much for reading this article.

Until next time, stay happy and question everything.